Radiology of hypothalamic lesions: A pictorial essay depicting characteristic hypothalamic pathologies Poster No.: C-2713 Congress: ECR 2010 Type: Scientific Exhibit Topic: Neuro Authors: A. J. B. Baxi, B. Murali, T. Nagendra, S. Vidyasagar, K. L. Tourani; Hyderabad/IN Keywords: Hypothalamus, [A08.186.211.577.482], pituitary adenoma,pituitary, diseases,mr imaging differential diagnosis(c19.344.609), Magnetic Resonance Imaging,primary imaging modalitydynamic scan (E01.370.350.825.5000 DOI: 10.1594/ecr2010/C-2713 Any information contained in this pdf file is automatically generated from digital material submitted to EPOS by third parties in the form of scientific presentations. References to any names, marks, products, or services of third parties or hypertext links to thirdparty sites or information are provided solely as a convenience to you and do not in any way constitute or imply ECR's endorsement, sponsorship or recommendation of the third party, information, product or service. ECR is not responsible for the content of these pages and does not make any representations regarding the content or accuracy of material in this file. As per copyright regulations, any unauthorised use of the material or parts thereof as well as commercial reproduction or multiple distribution by any traditional or electronically based reproduction/publication method ist strictly prohibited. You agree to defend, indemnify, and hold ECR harmless from and against any and all claims, damages, costs, and expenses, including attorneys' fees, arising from or related to your use of these pages. Please note: Links to movies, ppt slideshows and any other multimedia files are not available in the pdf version of presentations. www.myesr.org Page 1 of 89
Purpose Hypothalamus, the ventral-most portion of the diencephaion, surrounds the anterior inferior portion of the third ventricle (Fig. 1 & 2). Fig.: Fig1.Drawing shows the hypothalamus (outlined with a pink color)ac-anterior commissure,pc-posterior commissure,mb-mamillary bodies,pp-posterior pituitary,apanterior pituitary. References: B. Murali; Radiology, Care hospital, Hyderabad, INDIA Page 2 of 89
Fig.: Fig(1).T1 sagittal demonstrates anatomy of hypothalamus. AC-anterior commissure,pc-posterior commissure,mb-mamillary bodies, TC-tuber cinerium,isinfundibular stalk,oc-optic chiasma,pp-posterior pituitary gland. References: B. Murali; Radiology, Care hospital, Hyderabad, INDIA Page 3 of 89
Fig.: Fig(2).Sagittal T1 contrast- the infundibular stalk and pituitary gland show normal homogeneous enhancement, which reflects their lack of a blood-brain barrier. References: B. Murali; Radiology, Care hospital, Hyderabad, INDIA It functions primarily as an integrative mechanism for various autonomic and neuroendocrine activities including temperature regulation, water balance, behavior and appetite. There is variability concerning the appearance of hypothalamic lesions The hypothalamus is susceptible to involvement by a variety of processes, including developmental abnormalities, primary tumors of the central nervous system (CNS), vascular tumors, systemic tumors affecting the CNS, inflammatory and granulomatous disease. The hypothalamus may also be involved by lesions arising from surrounding structures such as the pituitary gland. Since the pathologic spectrum of hypothalamic disease is so diverse, knowledge of the imaging appearance of diseases specific to pituitary and hypothalamus is important for accurate diagnosis and treatment. The purpose is: Page 4 of 89
1. To describe the anatomy of the hypothalamus 2. To review Imaging features of various hypothalamic lesions. 3. To discuss differential diagnosis for hypothalamic lesions on MR imaging Images for this section: Page 5 of 89
Fig. 1: Fig(1).T1 sagittal demonstrates anatomy of hypothalamus. AC-anterior commissure,pc-posterior commissure,mb-mamillary bodies, TC-tuber cinerium,isinfundibular stalk,oc-optic chiasma,pp-posterior pituitary gland. Page 6 of 89
Fig. 2: Fig(2).Sagittal T1 contrast- the infundibular stalk and pituitary gland show normal homogeneous enhancement, which reflects their lack of a blood-brain barrier. Page 7 of 89
Fig. 3: Fig1.Drawing shows the hypothalamus (outlined with a pink color)ac-anterior commissure,pc-posterior commissure,mb-mamillary bodies,pp-posterior pituitary,apanterior pituitary. Page 8 of 89
Methods and Materials A retrospective review of our institutional case archive from 2002 to 2009 revealed broad range of neoplasms, inflammatory and infectious disorders, and congenital and developmental lesions. The region of study included hypothalamus, pituitary gland and parasellar region. Imaging were performed on 1.5 Tesla MRI with head coil, single slice CT, 6 slice CT and 64 slice CT scanner to characterize the pathologic spectrum of hypothalamic and parahypothalamic diseases with soft tissue and bony reconstruction whenever needed. Sagittal and coronal spin-echo T1-weighted sequences were performed with thin sections (3mm) and a small field of view (200-230mm). The axial sections were set at 4 mm thickness. The same sequence was repeated after the intravenous administration of a standard dose (0.2mmol/kg) of gadopentetate dimeglumine and 1 mm spacing.(fig1-3) Fig.: Sagittal localiserfor planning axial images References: B. Murali; Radiology, Care hospital, Hyderabad, INDIA Page 9 of 89
Fig.: Localiser for coronal planning References: B. Murali; Radiology, Care hospital, Hyderabad, INDIA Page 10 of 89
Fig.: Localizer for coronal planning References: B. Murali; Radiology, Care hospital, Hyderabad, INDIA All patients had sagittal T1, T2 weighted, axial T1, T2 weighted with fat saturation, Flair, coronal T1, Flair, and post-gadolinium axial, sagittal and coronal T1 weighted sequences. In addition, in some patients, sagittal dynamic image were also done if small pituitary and hypothalamic lesions were suspected. This dynamic study was done after rapid injection of gadopentetate dimeglumine. Page 11 of 89
Images for this section: Fig. 1: Sagittal localiserfor planning axial images Page 12 of 89
Fig. 2: Localiser for coronal planning Page 13 of 89
Fig. 3: Localizer for coronal planning Page 14 of 89
Results We were able to recognize the clinical manifestations and key MR imaging features of various hypothalamic lesions. We came across developmental abnormalities (craniopharyngioma, hamartoma, dermoid and epidermoid cysts, Rathke cleft cyst[rcc], colloid cyst, primary tumors of the central nervous system (CNS) (hypothalamic-chiasmatic glioma, Pituitary adenoma), systemic tumors affecting CNS, inflammatory and granulomatous diseases (lymphocytic hypophysitis) and lesions arising from surrounding structures. Of the total number of patient studied during 2003-2009, 127 patients had hypothalamic and juxtasellar lesions between the age of 4-75years.Of this, we excluded 20 patients who did not turn up for follow or refused surgery.107 cases of hypothalamic and juxtasellar abnormalities were pathologically or medically proved on follow up imaging. Pituitary macroadenoma : 52 cases Meningioma : 14 cases, Craniopharyngioma : 13 cases, Granulomatous disease: 5 cases, Metastatic disease : 4 cases, Chiasmatic glioma : 7 cases, Lymphocytic Infundibuloneurohypophysitis: 3 cases, Hypothalamic glioma : 3 cases, Dermoid : 2 cases, Rathke cleft cyst : 1 cases, Colloid cyst : 1 cases, Hypothalamic hamartoma : 2 cases. The MR imaging characteristics of most common lesions were sufficiently distinct to allow them to be differentiated from each other. Other characteristics such as extrasellar Page 15 of 89
versus intrasellar location, nature of contrast material enhancement, the presence of cystic components, bony changes and clinical findings permitted further differentiation among the various other abnormalities. Some hypothalamic lesions showed remarkable consistency in location, such as hamartoma. A thickened contrast-enhanced infundibulum is the most typical manifestation of, lymphocytic hypophysitis and sarcoidosis. Involvement of the optic chiasm and optic nerves by hypothalamic tumors may point to the diagnosis of hypothalamic-chiasmatic glioma. Larger hypothalamic lesions may extend into the pituitary fossa and parasellar region. The differential diagnosis for such lesions includes pituitary adenomas with suprasellar extension. However, the most common masses in the hypothalamic region in our experience were suprasellar pituitary adenoma, craniopharyngioma, and hypothalamic- chiasmatic glioma; other lesions like dermoid and hamartomas were less commonly seen. Contrast-enhanced MR imaging also helped in differentiating nonneoplastic cysts (eg, arachnoid, epidermoid, and colloid cysts) from cystic neoplasms (eg, RCC, craniopharyngioma, cystic pituitary adenoma) within the hypothalamic region. Unlike nonneoplastic cysts, cystic tumors usually show cyst wall enhancement. Contrast-enhanced MR imaging also showed a wide variety of enhancement patterns. Classically, hypothalamic hamartomas showed no contrast enhancement. This finding is fairly characteristic and is helpful in differentiating hamartomas from other lesions. Enhancement of other hypothalamic lesions ranged from homogeneous (germinoma) to patchy and irregular (craniopharyngioma, glioma). Associated findings of leptomeningeal enhancement with multiple foci of parenchymal enhancement pointed to infection / sarcoidosis. Enhancement pattern: No enhancement Hamartoma Rathke cleft cyst Dermoid cyst Epidermoid cyst Arachnoid cyst Colloid cyst Homogenous enhancement Page 16 of 89
Meningioma Germinoma Inhomogeneous enhancement Glioma Pituitary adenoma Peripheral enhancement Craniopharyngioma Individual lesions: Craniopharyngioma Arises from remnant of craniopharyngeal duct Anywhere from sella to 3rd ventricle Adamantinomatous type - 2nd decade ; calcification and cystic lesions are common Solid, papillary type - 5th decade Males 90% rule - children, cystic, calcification, suprasellar. Fig(1-3) Page 17 of 89
Fig.: Partially calcified sella mass- craniopharyngioma References: B. Murali; Radiology, Care hospital, Hyderabad, INDIA Page 18 of 89
Fig.: Craniopharangioma with cyst and calcification References: B. Murali; Radiology, Care hospital, Hyderabad, INDIA Page 19 of 89
Fig.: Craniopharangioma- Sag T2 References: B. Murali; Radiology, Care hospital, Hyderabad, INDIA Hypothalamic Hamartoma Developmental malformation Children Males Intrahypothalamic - gelastic seizures Parahypothalamic - tuber cinerum - precocious puberty Signals same as grey matter Isointense on Ti -weighted images and isointense or mildly hyper intense on T2-weighted images No cystic changes, no calcification, contrast enhancement. The lesions are stable in size over time. Page 20 of 89
Fig(4,5) Fig.: Saggital T1-Hypothalamic Hamartoma References: B. Murali; Radiology, Care hospital, Hyderabad, INDIA Page 21 of 89
Fig.: Non enhancing Hypothalamic hamartoma References: B. Murali; Radiology, Care hospital, Hyderabad, INDIA Hypothalamic chiastmatic glioma M=F 20-40years Suprasellar location Associated with NF1 Hypointense in T1, hyperintense in T2 Inhohogenous contrast enhancemen Fig6-7 Page 22 of 89
Fig.: Enhancing hypothalamic glioma. References: B. Murali; Radiology, Care hospital, Hyderabad, INDIA Lymphocytic Infundibuloneurohypophysitis Autoimmune inflammatory condition Adults,more in females wih hypopituitarism in peripartum period MR shows diffuse enlargement of hypothalamus and infundibulum Typically shows uniform contrast enhancement Fig8-10 Page 23 of 89
Fig.: Ti sagittal-diffuse enlargement of pituitary,infundibulum and hypothalamus. References: B. Murali; Radiology, Care hospital, Hyderabad, INDIA Page 24 of 89
Fig.: CE sagittal T1- lymphocytic hypophysitis.symmetric enlargement of the pituitary gland with homogeneous contrast enhancement. References: B. Murali; Radiology, Care hospital, Hyderabad, INDIA Page 25 of 89
Fig.: Lymphocytic hypophysitis-complete shrinkage of mass after high glucocorticoid dose References: B. Murali; Radiology, Care hospital, Hyderabad, INDIA Pituitary macroadenoma More or less isointense to the normal gland and brain parenchym Cystic or hemorrhagic components are present. Hemorrhage is depicted better by MR than CTand the signal characteristics suggest the age of the hemorrhage. Pituitary apoplexy, acute hemorrhagic necrosis of a macroadenoma, and patients may present with symptoms related to mass effect of the hematoma or associated subarachnoid hemorrhage Page 26 of 89
Macroadenomas - homogeneous enhancement and are clearly demarcated from normal suprasellar structures Fig11-12 Fig.: Pituitary macroadenoma with suprasellar extension References: B. Murali; Radiology, Care hospital, Hyderabad, INDIA Page 27 of 89
Fig.: Enhancing pituitary macroadenoma with suprasellar extension. References: B. Murali; Radiology, Care hospital, Hyderabad, INDIA Meningioma- Page 28 of 89
Suprasellar mass 40 to 50 year olds M>F Visual loss is the most common symptom CT shows a hyperdense lesion originating from the tuberculum sella, planum sphenoidale, or sphenoidal ridge with hyperostosis Isointense on precontrast T1-weighted images and with a bright enhancement after gadolinium contrast. A dural tail sign, on contrast T1 images, is suggestive of Meningioma. Fig13-14 Fig.: T1 isointense Meningioma References: B. Murali; Radiology, Care hospital, Hyderabad, INDIA Page 29 of 89
Fig.: Enhancing meningioma with dural tail sign References: B. Murali; Radiology, Care hospital, Hyderabad, INDIA Tuberculosis Pituitary tuberculomas are rare Most patients have other signs of active tuberculosis, Patients are affected at any age and there is female predominance Visual loss and headache are the most common symptoms MRI shows thickening of pituitary stalk with enhancement with granulomas in brain parenchyma Fig 15-16 Page 30 of 89
Fig.: TB granuloma involving hypothalamus,optic chiasma and optic tract References: B. Murali; Radiology, Care hospital, Hyderabad, INDIA Page 31 of 89
Fig.: TB granuloma involving hypothalamus,optic chiasma and optic tract. References: B. Murali; Radiology, Care hospital, Hyderabad, INDIA Colloid cyst Slow growing Neuroepithelial or endodermal origin Rare Suprasellar,usually anterosuperior to 3rd ventrical 5-6 decades Page 32 of 89
T1 hyperintensity,t2 iso-hypointensity No contrast enhancement or calcification. Fig 17-19 Fig.: Hyperdense colloid cyst on CT References: B. Murali; Radiology, Care hospital, Hyderabad, INDIA Page 33 of 89
Fig.: Colloid cyst on sagittal T2 References: B. Murali; Radiology, Care hospital, Hyderabad, INDIA Page 34 of 89
Fig.: Post contrast T1 image showing non-enhancing colloid cyst References: B. Murali; Radiology, Care hospital, Hyderabad, INDIA Dermoid cyst Inclusion c composed of ectodermal elementsusually Benign, slow-growing midline lesions Slight male predominance Young patients up to 20 years of age Page 35 of 89
Hypodence fat density lesion Hyperintense on T1-weighted images and hypointense on T2-weighted images. Fat-suppression techniques may be helpful in confirming the presence of fat in the lesion No contrast enhancement, Fig 20-21 Fig.: Dermoid cyst with fatty attenuation on CT References: B. Murali; Radiology, Care hospital, Hyderabad, INDIA Page 36 of 89
Fig.: Sag T1 image showing hyperintense dermoid cyst References: B. Murali; Radiology, Care hospital, Hyderabad, INDIA Page 37 of 89
Page 38 of 89
Page 39 of 89
Page 40 of 89
Page 41 of 89
Page 42 of 89
Page 43 of 89
Page 44 of 89
Page 45 of 89
Page 46 of 89
Page 47 of 89
Page 48 of 89
Page 49 of 89
Page 50 of 89
Page 51 of 89
Page 52 of 89
Page 53 of 89
Images for this section: Page 54 of 89
Fig. 1: Partially calcified sella mass- craniopharyngioma Page 55 of 89
Fig. 2: Craniopharangioma with cyst and calcification Page 56 of 89
Fig. 3: Craniopharangioma- Sag T2 Page 57 of 89
Fig. 4: Saggital T1-Hypothalamic Hamartoma Page 58 of 89
Fig. 5: Non enhancing Hypothalamic hamartoma Page 59 of 89
Fig. 6: Fig6-Bilateral opticochiasmatic hypothalamic glioma Page 60 of 89
Fig. 7: Enhancing hypothalamic glioma. Page 61 of 89
Fig. 8: Ti sagittal-diffuse enlargement of pituitary,infundibulum and hypothalamus. Page 62 of 89
Fig. 9: CE sagittal T1- lymphocytic hypophysitis.symmetric enlargement of the pituitary gland with homogeneous contrast enhancement. Page 63 of 89
Fig. 10: Lymphocytic hypophysitis-complete shrinkage of mass after high glucocorticoid dose Page 64 of 89
Fig. 11: Pituitary macroadenoma with suprasellar extension Page 65 of 89
Fig. 12: Enhancing pituitary macroadenoma with suprasellar extension. Page 66 of 89
Fig. 13: T1 isointense Meningioma Page 67 of 89
Fig. 14: Enhancing meningioma with dural tail sign Page 68 of 89
Fig. 15: TB granuloma involving hypothalamus,optic chiasma and optic tract Page 69 of 89
Fig. 16: TB granuloma involving hypothalamus,optic chiasma and optic tract. Page 70 of 89
Fig. 17: Hyperdense colloid cyst on CT Page 71 of 89
Fig. 18: Colloid cyst on sagittal T2 Page 72 of 89
Fig. 19: Post contrast T1 image showing non-enhancing colloid cyst Page 73 of 89
Fig. 20: Dermoid cyst with fatty attenuation on CT Page 74 of 89
Fig. 21: Sag T1 image showing hyperintense dermoid cyst Page 75 of 89
Fig. 22: Rathke cleft cyst. Page 76 of 89
Fig. 23: Radiation necrosis of optic chiasma following radiotherapy for pituitary adenoma Page 77 of 89
Fig. 24: Radiation necrosis of optic chiasma following radiotherapy for pituitary adenoma shows enhancement of residual tumor Fig. 25: Hypothalamic encephilitis. Page 78 of 89
Fig. 26: Hypothalamic encephilitis. Page 79 of 89
Fig. 27: Hypothalamic encephilitis. Page 80 of 89
Fig. 28: Aspergillous granuloma.plain CT shows hyperdense lesion in sellar region,middile cranial and posterior cranial fossa with mastoiditis Page 81 of 89
Fig. 29: Aspergillous granuloma extending into middle and posterior cranial fossa Page 82 of 89
Fig. 30: Aspergillous granuloma secondary to sinusitis and mastoiditis. Page 83 of 89
Fig. 31: Hypothalamic glioma Page 84 of 89
Fig. 32: Craniopharyngioma showing peripheral enhancement. Page 85 of 89
Fig. 33: Pituitary macroadenoma with hemorrhage. Page 86 of 89
Conclusion Knowledge of the imaging appearance of diseases specific to pituitary and hypothalamus is important for accurate diagnosis and treatment.the spectrum of pathology involving the hypothalamus is broad yet distinct from other pathology in the sella and parasellar region. The hypothalamus presents a diagnostic imaging challenge because of its small size and protea spectrum of disease processes. Congenital and developmental abnormalities usually have characteristic findings on imaging. Primary glial tumors have distinct different clinical course; therefore, including such tumors in the differential diagnosis of hypothalamus masses has implications for correct histopathologic diagnosis and treatment. Inflammatory disorders are likely underrecognized as a cause of masses of the hypothalamus in adults. Their inclusion in the differential diagnosis of adult hypothalamus disease is important because it may allow the option for noninvasive treatment and improved clinical course, particularly in patients with INH or adenohypophysitis. MR imaging is an excellent noninvasive modality for evaluation of the hypothalamus and pituitary gland. It not only depicts anatomy of pituitary gland, infundibulum, optic chiasm, cavernous sinuses, and neighboring vascular structures but also helps in identifying there pathologies and thus aids in differential diagnosis. The addition of gadolinium further facilitates diagnosis and increases the confidence level especially when concerned regarding invasion of adjacent structures and cavernous sinus. Visualization of vascular parasellar structures such as intrasellar carotid artery loop or aneurysm is also clearly seen, which is crucial in some cases. The specific bony landmarks are sometimes difficult to demonstrate on MRI, but T2 Fat saturated sequence coupled with contrast study, gives sufficient information. However, CT scanning still holds the edge in evaluating bony abnormalities. References Gray H. Anatomy of the human body. Philadelphia, Pa: Lea & Febiger, Page 87 of 89
1918; Bartleby.com, 2000. MR Anatomy and Pathology of the Hypothalamus. D.J. Loes, Thomas J. Barloon, William T.C.Yuh, Robert L.,1991 Lesions of the Hypothalamus: MR Imaging Diagnostic Features Sahar N. Saleem, MD, P hd et al RadioGraphics 2007; 27: 1087-1108, 2007 Neuroendocrine ImagingD. David J. Seidenwurm, MD, Principal Author, Radiologic Associates of Sacramento, Sacramento,AJNR 29:613-15 :Mar 2008. Diagnostic Neuroradiology: Anne G Osborn,MD. Imaging of Pediatric Pituitary Abnormalities:Bradley N. Delman, MD. Diagnostic Imaging:Head and Neck, Harnsberger MD. et al,isbn,2006-2007. Diagnostic Imaging -Brain,Osborn MD,et al,1st edition,2005. Clinical MRI -Vol 2,Edelman et al,3rd edition. Personal Information Dr.Belman Murali MD, Cosultant Radiologist, Institute of Radiology and Imaging Sciences (IRIS) Page 88 of 89
Care Hospitals, Road number 1, Banjara Hills, Hyderabad 500033 Andhra Pradesh India. Email: drbelmanmurali@gmail.com Page 89 of 89